Long cool-down tube with air input joints

ABSTRACT

A conduit system comprising: a conduit formed by a surface extending from a first end to a second end, wherein the conduit is configured to channel a mixture stream from the first end to the second end; and a plurality of fluid delivery features disposed along the conduit between the first end and the second end, wherein each fluid delivery feature is configured to deliver a conditioning fluid into the conduit in an annular formation in a direction angled towards the second end in the same direction as the flow of the mixture stream, thereby providing a sheath of conditioning fluid between the conduit surface and the mixture stream.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims to co-pending U.S. ProvisionalApplication Ser. No. 60/928,946, filed May 11, 2007, entitled “MATERIALPRODUCTION SYSTEM AND METHOD,” which is hereby incorporated by referenceas if set forth herein. The co-pending U.S. patent application Ser. No.11/110,341, filed on Apr. 10, 2005, entitled, “HIGH THROUGHPUT DISCOVERYOF MATERIALS THROUGH VAPOR PHASE SYNTHESIS” is incorporated byreference.

FIELD OF THE PRESENT INVENTION

The present invention relates to methods of cooling and controlling theflow of a hot, reactive medium containing gas or vapor phase particles.

BACKGROUND OF THE PRESENT INVENTION

Gas or vapor phase particle production is an important technique forproducing engineered materials, especially nanomaterials. Specificcharacteristics of particles produced in gas or vapor phase synthesisreactions depend not only on the energy delivered to the reactivemedium, but also on the conditioning of the reactive medium once themedium has left the reactor.

In a particle production reactor, basic product species are formedwithin extremely short time spans as the reactive medium cools followingejection from the energy delivery zone. During the time followingejection, further formation mechanisms determine the ultimatecharacteristics of the final product.

Chemical reactions such as nucleation and surface growth occur withinprecursor materials largely during energy delivery. However, theseformation mechanisms continue to be active in the first short momentsfollowing ejection. More prevalent in the post-ejection time period arebulk formation mechanisms, such as coagulation and coalescence, whichoperate on already formed particles. Proper conditioning of the reactivemedium following ejection from the energy delivery zone accounts forthese and other formation mechanisms to control formation of a finalproduct having desired characteristics.

In addition to particle formation, proper conditioning must account forpost-formation processing of the product. Although particles, onceformed, cool rapidly through radiative heat loss, the residual gas inwhich they are entrained after formation cools much more slowly, andespecially so when confined. Confinement is necessary to some degree inany controlled-environment processing system, and economic concernsusually dictate relatively confining controlled environments becauselarge environments cost more to build and maintain. Because supplysystems require product sufficiently cool for handling, such systemsmust provide efficient mechanisms for cooling of the entire gas-particleproduct, yet also provide for efficient transport of the product tocollection points within the system. They must also preventagglomeration of the particles beyond a certain point or time period toensure proper grain size in the final product.

Transport of particles within a gas stream relies on entrainment of theparticle, which is largely a function of particle properties, includingmass, temperature, density, and interparticle reactivity, as well as gasproperties, including density, velocity, temperature, viscosity, andcomposite properties, such as particle-gas reactivity. Cooling of a gasby definition affects gas temperature, but also may easily lead tochanges in other properties listed above, exclusive of mass. In view ofthis, balancing efficient cooling and transport of gas-particle productrequires careful optimization of process parameters, which the presentinvention seeks to achieve.

SUMMARY OF THE PRESENT INVENTION

According to the present invention, a conduit system for transportingparticle and gas mixtures is presented. The conduit system is primarilyintended to condition and conduct gas particle product emitted from gasphase particle production reactors, such as flame reactors, plasmareactors, hot wall reactors and laser reactors. Conditioning performedwithin the system includes cooling of gas-vapor mixtures and maintainingentrainment of particles therein for sampling and collection. Theconditioning performed within the present invention accounts forparticle interaction mechanisms within the gas particle mixture.

The conduit system comprises a conduit defining a flow direction from afirst end to a second end and including a plurality of fluid deliveryfeatures. The fluid delivery features each include a port in theinterior surface of the conduit, and are spaced along the conduit. Theports allow communication between the exterior and the interior of theconduit.

The conduit system works to cool, deliver and further condition areactive gas-particle mixture produced by a gas phase particleproduction reactor. In operation, a hot gas-particle mixture tends toexpand as it flows through the conduit. Expansion of the gas-particlemixture against the inner surfaces of the conduit can lead to adhesionthereto by particles and subsequently to the deposit of residues withinthe conduit. This pollution of the conduit can affect fluid flow withinthe conduit and can contaminate subsequent gas-particle mixtures flowingin the conduit.

The occurrence of significant deposits would make regular cleaning ofthe conduit necessary to ensure proper operation. Cleaning can requiredeactivation of the equipment and reduce the efficiency of the process,thereby resulting in increased expense and decreased productivity.

However, occurrence of residue is minimized by the present invention, inwhich conditioning fluid flows into the conduit through the pluralityfluid delivery features, providing a sheath of conditioning fluidbetween the gas-particle mixture and the inner surfaces of the conduit.Preferably, the conditioning fluid flows symmetrically through one ormore ports into the conduit. Symmetric inflow of conditioning fluidconstricts the flow of the gas-particle mixture and reinforces theconditioning fluid sheath in the region of each fluid delivery feature.Preferably, fluid delivery features provide conditioning fluid regularlyenough so that complete intermixture of the gas-particle mixture withthe conditioning fluid sheath never occurs. The conditioning fluid ispreferably provided at a cooler temperature than the gas-particlemixture and substantially prevents the gas-particle mixture fromencountering the inner surfaces of the conduit. In a further aspect, thetemperature of the region of the conduit surrounding each fluid deliveryfeature can be controlled to aid in conditioning the gas-particlemixture and to prevent deposition of particles thereon.

A specific conditioning fluid is selected for its intrinsic properties.Desired intrinsic properties depend to an extent on the specific mixturebeing conducted through the conduit. For example, typically inertgasses, such as argon, neon, and helium, are preferred for theirnear-non existent reactivity. Among inert gasses, argon is morepreferred than helium or neon because it provides a more effectivesheath. Furthermore, extrinsic properties, such as temperature anddensity, correlate to the ability of the conditioning fluid to cool andcondition the gas-particle mixture and are controlled to provide desiredlevels of cooling and conditioning to the gas-particle mixture.

Although the specific mixture under consideration partially determinesthe conditioning fluid used and the selection of the extrinsic fluidproperties, the location of fluid introduction also must be considered.In one embodiment, the conditioning fluid introduced through thefeatures closer to the particle source is different than the fluidintroduced through the features farther from the particle source. Forexample, a first gas can be introduced through the features closer tothe injection end of the conduit, while a second gas can be introducedthrough the features farther away from the injection end. In alternativeembodiments, the same type of conditioning fluid is introduced througheach fluid delivery feature, but extrinsic properties of the fluid, suchas temperature, are varied according to the delivery location. Theconditioning fluid introduced through each feature in the set of fluidintroduction features is preferably chosen to balance the competingconcerns of economic efficiency and high product quality. Preferably,the conditioning fluid is supplied passively, as described more fullybelow, through a neutral pressure environment formed around fluiddelivery ports within the conduit. Furthermore, the conduit isconfigured so that the conditioning fluid flows at a rate sufficient tomaintain entrainment of the particles within the gas flow.

Therefore, the present invention provides a flowing sheath ofconditioning gas along the inner walls of a conduit through which agas-particle mixture flows. As the conditioning gas and the gas-particlemixture flow through the conduit, the introduction of fresh conditioninggas maintains entrainment of the particles and cools the gas-particlemixture.

In one aspect of the present invention, a conduit system is provided.The conduit is formed by a surface extending from a first end to asecond end. The conduit is configured to channel a mixture stream fromthe first end to the second end. A plurality of fluid delivery featuresare disposed along the conduit between the first end and the second end.Each fluid delivery feature is configured to deliver a conditioningfluid into the conduit in an annular formation in a direction angledtowards the second end in the same direction as the flow of the mixturestream, thereby providing a sheath of conditioning fluid between theconduit surface and the mixture stream.

In another aspect of the present invention, a method of conditioning amixture stream is provided. The method comprises providing a conduitformed by a surface extending from a first end to a second end. Aplurality of fluid delivery features are disposed along the conduitbetween the first end and the second end. The mixture stream flowsthrough the conduit from the first end to the second end. A conditioningfluid is delivered into the conduit while the mixture stream flowsthrough the conduit. The conditioning fluid is delivered through aplurality of delivery features disposed along the conduit between thefirst end and the second end. Each fluid delivery feature delivers theconditioning fluid into the conduit in an annular formation in adirection angled towards the second end in the same direction as theflow of the mixture stream, thereby providing a sheath of conditioningfluid between the conduit surface and the mixture stream.

In preferred embodiments, each fluid delivery feature comprises a portsstructure and an annular housing. The port structure is fluidly coupledto the interior of the conduit and is configured to deliver theconditioning fluid into the conduit in an annular formation in adirection angled towards the second end in the same direction as theflow of the mixture stream. The annular housing is disposed around theconduit and covers the port structure. The annular housing comprises afluid supply port configured to supply the conditioning fluid to theport structure for delivery into the conduit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are systematic views of two embodiments of a conduitsystem integrated into particle processing systems in accordance withthe principles of the present invention.

FIG. 2 is a schematic cross-sectional view of one embodiment of aconduit system in accordance with the principles of the presentinvention.

FIG. 3 is a cross-sectional view of one embodiment of a conduit couplerin accordance with the principles of the present invention.

FIG. 4 is a flowchart illustrating one embodiment of a method ofconditioning a reactive mixture in accordance with the principles of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

The description below concerns several embodiments of the invention. Thediscussion references the illustrated preferred embodiment. However, thescope of the present invention is not limited to either the illustratedembodiment, nor is it limited to those discussed. To the contrary, thescope should be interpreted as broadly as possible based on the languageof the Claims section of this document.

In the following description, numerous details and alternatives are setforth for purpose of explanation. However, one of ordinary skill in theart will realize that the invention can be practiced without the use ofthese specific details. In other instances, well-known structures anddevices are shown in block diagram form in order not to obscure thedescription of the invention with unnecessary detail.

This disclosure refers to both particles and powders. These two termsare equivalent, except for the caveat that a singular “powder” refers toa collection of particles. The present invention may apply to a widevariety of powders and particles. Powders that fall within the scope ofthe present invention may include, but are not limited to, any of thefollowing: (a) nano-structured powders(nano-powders), having an averagegrain size less than 250 nanometers and an aspect ratio between one andone million; (b) submicron powders, having an average grain size lessthan 1 micron and an aspect ratio between one and one million; (c)ultra-fine powders, having an average grain size less than 100 micronsand an aspect ratio between one and one million; and (d) fine powders,having an average grain size less than 500 microns and an aspect ratiobetween one and one million.

The present invention will be readily understood by the followingdetailed description in conjunction with the accompanying drawings. Tofacilitate this description, like reference numerals designate likeelements.

The present invention includes a plurality of fluid delivery features.Each fluid delivery feature preferably includes one or more portsconfigured to deliver a symmetrical sheath of conditioning fluid.Although the specific details of the fluid delivery features aredetermined within each embodiment, largely with reference to the typesof fluids and particles the embodiment is designed to deal with, thegenerally preferred configuration of the ports is discussed in thefollowing paragraphs. Furthermore, the operation of the fluid deliveryfeatures and the effect of fluid and particle parameters on their designare also discussed.

The ports allow communication between the exterior and the interior ofthe conduit. Preferably, each port is configured to deliver conditioningfluid evenly and along the inner surface of the conduit substantially inthe direction of flow within the conduit. Two structural features arepreferably present in each fluid delivery feature: the ports are angledalong the flow direction of the conduit, and each port delivers fluidalong the entirety of an inner cross-sectional boundary of the conduit.Fluid can be delivered evenly or unevenly along the entirety of theinner cross-sectional boundary. In one embodiment, uneven fluid deliveryis used to counteract the influence of gravity on the entrainedparticles.

The first structural feature results in an angled path of fluid flowinto the conduit through the ports. Introducing conditioning fluid alongan angled path results in less significant disturbances to thegas-particle mixture flowing through the interior ‘core’ of the conduit,resulting in little additional turbulence therein. As discussed below,less significant perturbation of the gas-particle mixture results inless efficient cooling, but succeeds in minimizing particle depositionwithin the conduit. Although a less-angled path of fluid flow moreparallel to the direction of flow within the conduit may be preferred insome applications, the present invention prefers an angular path ofdelivery to allow for constriction of the gas-particle mixture flow.

The second preferred structural feature, each port delivering fluidalong the entirety or substantial entirety of an inner cross-sectionalboundary of the conduit, seeks to maximize effectiveness of theconditioning gas as a sheath between the gas-particle mixture and theinner surface of the conduit. The present invention contemplates myriadways of accomplishing this goal. In one aspect, each port is formed froma plurality of sub-ports, each shaped to provide fluid flow along asmall portion of the inner surface. The sub-ports are tapered, offset orotherwise situated so that sufficient material remains within theconduit to provide structural stability around the port. In a furtheraspect, one continuous port is provided within the inner surface of theconduit and an external housing is coupled to the conduit to providestructural support in the region of the port. In this aspect, thehousing may also provide a fluid reservoir where conditioning fluid isheld and allowed to flow into the port.

Furthermore, each port is preferably in fluid communication with areservoir containing conditioning fluid. In the preferred embodiment ofthe present invention, the reservoir is integrated into a housingsurrounding a port of a fluid delivery feature in the conduit. In thisaspect, the housing provides structural support to the conduit. Inalternative embodiments, the reservoir is simply a manifold forconditioning fluid delivery and does not provide structural support tothe conduit. In a further alternative embodiment, the reservoir is achamber sealed with the conduit and surrounding a structural housingincluding a fluid supply port. In each aspect, the reservoir is sealedto the conduit. Exemplary seals include high temperature o-ring seals,pressure fitted seals, and integral constructions.

Conditioning fluid is preferably supplied to the reservoir through asupply port exposed to the reservoir. The reservoir preferably has thesmallest possible volume while still maintaining sufficient spacetherein to allow uninterrupted flow of conditioning fluid into theconduit, so long as conditioning fluid is maintained at appropriatepressure, as will be discussed more fully below. In alternativeembodiments, conditioning fluid is supplied directly from a fluidmanifold to the port, or to each sub-port where the port comprises morethan one sub-port with no intervening reservoir.

The present invention contemplates a variety of constructions for theconduit system, including fully modular constructions, fully integratedconstructions, and combinations thereof. In an exemplary modularconstruction, the conduit system is pieced together from a plurality ofcomponents, each belonging to one of two component types: conduitpieces, and couplers.

The conduit pieces contemplated are simply lengths of conduit havingsubstantially constant cross sectional dimensions. Preferably theseconduit pieces have lengths substantially greater than theircross-sectional dimensions. Furthermore, these conduit pieces arepreferably actively cooled by a heat exchanger.

Couplers join multiple conduit pieces together. Preferably, two adjacentconduit pieces are joined by one coupler. The couplers include the fluiddelivery features mandated in the present invention. Specifically, amodular conduit coupler comprises a first and a second end eachconfigured to couple with a conduit piece. Between the first and secondends, one or more ports are formed to deliver fluid into the coupler.Furthermore, a fluid reservoir is preferably coupled with the one ormore ports formed in the coupler. In an additional aspect, the one ormore ports can have a variable total surface area.

In one particular embodiment, a coupler comprises two cylindrical pieceswith substantially similar outer cross-sectional dimensions and eachhaving one chamfered edge configured so that the chamfered edges aremateable and positioned a gap distance from one another to form a gaptherebetween. The coupler also comprises a third cylindrical piececonfigured to mate with the exterior surfaces of the two cylindricalpieces to effectively couple the two pieces with one another such thatthe third cylindrical piece covers the gap, the third piece has apassageway therein for supplying fluid to the gap. Furthermore, thethird piece can be slidably configured to adjust the total surface areaof the gap, and thus adjust the flow volume of conditioning fluid intothe conduit.

Preferably, the conduit has the following general dimensionalcharacteristics. The spacing between the fluid delivery features issubstantially larger than the cross-sectional dimension of the conduit,and the outer cross-sectional dimension of the conduit is substantiallyconstant over its length. Furthermore, the fluid delivery features arepreferably spaced evenly along the conduit. However, the presentinvention contemplates other spacings.

In a preferred embodiment, the ratio between the cross-sectionaldimension and the fluid delivery spacing is approximately 1 to 36. Morespecifically, the conduit preferably has a cross-sectional dimension ofapproximately 2 inches, and the preferable spacing between fluiddelivery features is approximately 6 feet.

As described above, a purpose of regularly introducing conditioning gasis to maintain entrainment of particles within the gas-particle mixtureand to prevent deposition of particles on the surfaces of the conduit.The likelihood of particle deposition within the conduit increases asintermixture of the gas-particle mixture with the sheath of conditioninggas occurs. Ideally, the gas-particle mixture is confined to the inner‘core’ of the conduit. Preferably, the sheath of conditioning gassurrounds the gas-particle mixture ‘core’ and insulates the conduitsurfaces from interaction with particles. Without regular introductionof conditioning gas, particle deposits within the conduit may occur. Thespecific regularity of introduction necessary is largely determined bythe particular gas-particle mixture. Conduit systems in accordance withthe present invention differ in the spacing of their fluid deliveryfeatures according to the gas-particle mixture for which they aredesigned, and in other aspects as well. Furthermore, the extrinsicproperties, e.g., temperature and pressure, of the conditioning gas arecontrolled to maintain entrainment of the particles within thegas-particle mixture.

In the present invention, the spacing between fluid delivery features isdetermined with a goal of preventing full intermixture between theconditioning gas sheath and the gas-particle mixture at any point in theconduit. Intermixture between the gas-particle mixture and theconditioning gas depends on many factors including temperature, particleproperties, density, velocity, viscosity, both of the mixture and of theconditioning gas.

Another aspect of conduit system design directed to maintaining particleentrainment is the spacing of the fluid delivery features. Regularintroduction of fresh conditioning gas is preferred to maintainintegrity of the sheath of conditioning gas. As the gas-particle mixtureand surrounding sheath of conditioning gas travel away from a fluiddelivery feature, they tend to intermix: increasing intermixture of thesheath gas and the core of gas-particle mixture leads to undesiredinteractions between the particles and the surfaces of the conduit.

Although, as described above, regular introduction of conditioning fluidis preferred within the present invention, the inclusion of multipledifferent spacings is also contemplated. As described earlier, theconditioning fluid sheath loses integrity and stops functioning due tointermixture of the gas-particle mixture and the sheath. When thetemperature difference between the conditioning gas sheath and thegas-particle mixture is greater, the two fluids mix more rapidly, e.g.,within a shorter distance of conduit, following introduction of theconditioning fluid. Therefore, because the particle-gas mixture cools asit flows through the conduit, the frequency of introduction for somesystems can be lessened farther along the conduit in the direction offlow. In other words, the spacing of the fluid delivery features canincrease along the conduit in the direction of flow.

The flow of the conditioning gas into the fluid delivery features ispreferably caused by formation of a negative pressure differential alongthe conduit, which also aids in maintaining flow of the mixture withinthe conduit. This negative pressure differential is preferably formed bycoupling a vacuum formation system with the end of the conduit.Alternatively, the negative pressure differential is formed by drawingfluid from a distal end of the conduit. In further alternativeembodiments, active injection of conditioning fluid is contemplated.

Furthermore, the conduit is preferably engineered so that any depositionof particles within the conduit will be relatively permanent withrespect to the gas-particle stream. In other words, no significantvariation in stream flow rate or strength occurs whereby anearlier-deposited particle might be re-entrained into the stream.Substantially constant fluid flow rates also promote more ‘permanent’deposition. Accordingly, operation of the vacuum system or other flowcontrol system must be carefully controlled.

Referring now to FIG. 1A, a particle processing system 100 incorporatesan embodiment of the present invention. The particle processing system100 preferably includes a gas-particle mixture production system 110fluidly coupled with a vacuum system 160 through a conduit system 120.In a preferred embodiment, a sampling zone 150 is fluidly coupledbetween the conduit system 120 and the vacuum system.

Some embodiments of the present invention revolve around the use of anano-powder production reactor. In general, vapor phase nano-powderproduction means are preferred. The mixture production system 110 canuse elements of nano-powder production systems similar to thosedisclosed in U.S. patent application Ser. No. 11/110,341, filed on Apr.19, 2005 and entitled, “HIGH THROUGHPUT DISCOVERY OF MATERIALS THROUGHVAPOR PHASE SYNTHESIS”, which is currently published as U.S. PublicationNo. 2005-0233380-A. In such a nano-powder production system, working gasis supplied from a gas source to a plasma reactor. Within the plasmareactor, energy is delivered to the working gas, thereby creating aplasma. A variety of different means can be employed to deliver thisenergy, including, but not limited to, DC coupling, capacitive coupling,inductive coupling, and resonant coupling. One or more materialdispensing devices introduce at least one material, preferably in powderform, into the plasma reactor. The combination within the plasma reactorof the plasma and the material(s) introduced by the material dispensingdevice(s) forms a highly reactive and energetic mixture, wherein thepowder can be vaporized. This mixture of vaporized powder moves throughthe plasma reactor in the flow direction of the working gas.

Referring back to FIG. 1A, the gas-particle mixture production system110 preferably produces particles entrained within a gas stream andprovides the output mixture stream to the conduit system 120. Thegas-particle mixture flows through the conduit 140 of the conduit system120, where it is conditioned and conducted to the sampling zone 150.Within the sampling zone 150 portions of the gas-particle mixture areseparated and the particles therein isolated for further analysis. Thebulk of the gas-particle mixture flows through the sampling zone andinto the vacuum system 160. The vacuum system 160 functions to draw thegas-particle mixture from the production system 110 through the conduitsystem 120, forcing it through the sampling zone 150.

The conduit system 120 conducts and processes the gas-particle mixture,maintaining entrainment of particles within the mixture by bothphysically processing the mixture and by surrounding the mixture with aconditioning fluid sheath. Aspects of the physical processing performedby the conduit system 120 are discussed in more detail later in thispaper. To form a sheath around the gas-particle mixture, theconditioning fluid is provided through a plurality of port structures141, 143, and 145 formed within the conduit 140. In a preferredembodiment, a conditioning fluid reservoir system 130 deliversconditioning fluid through the fluid delivery lines 132, 134, and 136 tothe respective conditioning fluid delivery chambers 142, 144, and 146 ofthe conduit structure 120. The conditioning fluid delivery chambers 142,144, and 146 respectively surround the port structures 141, 143, and145. In one embodiment of the present invention, the fluid reservoirsystem 130 comprises a single fluid reservoir containing a single typeof conditioning fluid which flows through each of the fluid deliverylines 132, 134, and 136. In alternative embodiments, the fluid deliverystructure comprises multiple reservoirs, each containing possiblydifferent types of conditioning fluid that are delivered through theconditioning fluid lines 132, 134, and 136 to the conditioning fluiddelivery chambers 142, 144, and 146 respectively. As described earlier,in some instances the present invention contemplates varying both thetype, and the physical properties of the conditioning gas based on thelocation of the fluid delivery port under consideration. The variousembodiments of the conditioning fluid delivery system 130 are configuredbased on the type of variation desired.

In one embodiment, the fluid delivery chambers 142, 144, and 146 aredisposed within housings that provide structural support to the conduit140. In alternative embodiments, the fluid delivery chambers 142, 144,and 146 are sealed reservoirs that do not provide structural support tothe conduit 140, but instead, the port structures 141, 143, and 145comprise structural elements. In either case, the fluid deliverychambers 142, 144, and 146 are preferably sealed with the conduit 140via bonding, pressure fitting, integral formation, or construction usinga high temperature o-ring seal.

The repeated introduction of conditioning gas, combined with the lengthof travel from the production system 110 and the physical processingdiscussed more thoroughly elsewhere, combine to cool and conduct the gasto the sampling zone 150, while maintaining entrainment and minimizingdeposition of the particles within the conduit system 120. The samplingzone 150 includes the sampling device 155 coupled with the conduitsystem 120 to separate a portion of a gas-particle mixture flowingtherein. In aspects of the present invention, the sampling device 155has an optimal operating temperature range for the sampled gas-particlemixture. Preferably, the conduit system 120 and the sampling zone 150are configured to cool the gas-particle mixture to within the optimaloperating temperature range of input for the sampling device 155.Configuration parameters for the conduit system 120 include overalldistance from the production system 110 to the sampling zone 150, thenumber and frequency of ports, and the type of conditioning gasintroduced into the ports.

It is contemplated that the sampling device 155 can be configured in avariety of ways. In one embodiment, the sampling device 155 comprises asampling structure, at least one filled aperture formed in the samplingstructure, and at least one unfilled aperture formed in the samplingstructure. Each filled aperture is configured to collect particles fromthe mixture stream, such as by using a filter. The sampling structure isconfigured to be adjusted between a pass-through configuration and acollection configuration. The pass-through configuration comprises anunfilled aperture being fluidly aligned with a conduit, such as conduit140, thereby allowing the unfilled aperture to receive the mixturestream from the conduit and the mixture stream to flow through thesampling structure without substantially altering the particle contentof the mixture stream. The collection configuration comprises a filledaperture being fluidly aligned with the conduit, thereby allowing thefilled aperture to receive the mixture stream and collect particleswhile the mixture stream is being flown through the filled aperture.

It is contemplated that the sampling structure can be adjusted betweenthe pass-through configuration and the collection configuration in avariety of ways. In one embodiment, the sampling structure is adisk-shaped structure including an annular array of apertures, whereinthe annular array comprises a plurality of the filled apertures and aplurality of the unfilled apertures. The sampling structure is rotatablymounted to a base, wherein rotational movement of the sampling structureresults in the adjustment of the sampling structure between thepass-through configuration and the collection configuration. In anotherembodiment, the sampling structure is a rectangular-shaped structureincluding a linear array of apertures, wherein the linear arraycomprises a plurality of the filled apertures and a plurality of theunfilled apertures. The sampling structure is slideably mounted to abase, wherein sliding of the sampling structure results in theadjustment of the sampling structure between the pass-throughconfiguration and the collection configuration.

As shown in FIG. 1A, the fluid delivery chambers 142, 144, and 146 canbe regularly spaced. However, the fluid delivery chambers of the presentinvention need not be evenly spaced. For example, in FIG. 1B, the fluiddelivery chambers 142′, 144′, and 146′ are unevenly spaced. Preferably,the spacing of the fluid delivery chambers is determined with referenceto the type of gas-particle mixture the conduit system 120 is designedto conduct. As discussed more fully below, the frequency of introductionof conditioning gas relates to the maintenance of entrainment ofparticles within the gas-particle mixture.

Referring now to FIG. 2, the physical processing of a conductedgas-particle mixture by a conduit system in accordance with the presentinvention is discussed. A conduit system 200 includes a plurality offluid delivery features 210, 220, and 230. In a preferred embodiment,the fluid delivery features are fluidly coupled with one or more fluidreservoirs (not shown) containing conditioning fluid as described andshown earlier with reference to FIG. 1.

Each fluid delivery feature 210, 220, 230 preferably includes a portstructure 214, 224, 234 with which a fluid reservoir is coupled tointroduce conditioning fluid into the conditioning fluid stream 260within the conduit structure 200 as described above. The introduction ofconditioning fluid in a symmetric distribution from the port structures214, 224, 234 around the gas-particle mixture stream 270 causesconstriction of the gas-particle mixture stream 270 at the constrictionpoints 216, 226, 236. After the constriction of the gas particle mixturestream 270, the mixture stream 270 will begin to mix with theconditioning fluid stream 260 and expand toward the interior wall of theconduit 242 after a period of time. Preferably, the next port structurewill constrict the gas-particle mixture stream 270 before it expands tocompletely fill the conduit 242. Both the conditioning fluid stream 260and the gas-particle mixture stream 270 flow in the direction of thearrow 250. The motive force determining this flow direction ispreferably an external low pressure source, such as a vacuum asdiscussed elsewhere. However, it is contemplated that the motive forcecan be provided in other ways as well.

As the gas-particle mixture 270 flows through the fluid deliveryfeatures 210, 220, 230, the conditioning fluid delivery promotesentrainment of particles within the flowing mixture 270 and preventscontamination of conduit system 200. By providing an insulating layerbetween the gas-particle mixture and the inner surfaces of the conduitsystem 200, delivery of conditioning fluid substantially preventsdeposition thereon of particles and subsequent contamination.

As mentioned earlier, if deposition does occur, the configuration offluid delivery features 210, 220, 230, combined with substantiallyconstant fluid flow, substantially prevents deposited content fromre-entraining into the flow of fluid within the conduit system 200.Thus, under desired operating conditions, particles do not reenter thestream once deposited.

Although the fluid delivery features 210, 220, and 230 appearsubstantially identical as illustrated, the present inventioncontemplates modifying the shapes and configurations thereof accordingto their relative spacing along the flow direction of the conduit system200.

Referring now to FIG. 3, one embodiment of a conduit coupler 300incorporates a fluid delivery feature in accordance with the presentinvention. The conduit coupler 300 comprises three subsections 310, 320,and 330. In a preferred embodiment, the conduit subsections 310 and 320are subsections of a conduit, such as conduit 242 in FIG. 2. Preferably,conduit subsections 310 and 320 are mateably configured and coupled withone another by the annular housing subsection 330. It is noted thatreference to the conduit of the present invention within this disclosureshould be interpreted to span across all conduit subsections, so that afirst end of the conduit can be on one subsection, while the second endof the conduit can be on a different subsection. In a preferredembodiment, the conduit subsections 310 and 320 are substantiallycylindrical in shape, having a constant inner diameter 311, preferablyequal to approximately 2 inches. The exterior surface of the conduitsubsection 310 can include the feature 314 configured to mate with theannular housing subsection 330. In a preferred embodiment, matingfeature 314 is an indentation formed circumferentially around theconduit. Furthermore, the conduit subsection 310 can include a chamferedend 316. The chamfered end 316 is configured opposite of the oppositelychamfered end 326 of the conduit subsection 320. The chamfered ends 316and 326 preferably form a channel 360 between the two. The conduitsubsection 320 can also include a feature 324, similar to feature 314,configured to mate with the annular housing subsection 330. In apreferred embodiment, both the inner and outer surfaces of the twoconduit subsections 310 and 320 are substantially similar.

The annular housing subsection 330 can include a relieved portion 334configured to form a fluid supply chamber 340 when the annular housingsubsection 330 mates with the conduit subsections 310 and 320.Preferably, the mating between the conduit subsections 310, 320 and theannular housing subsection 330 is accomplished by a press fit, afriction fit or other similar means. The fluid supply chamber 340 ispreferably arranged circumferentially around the conduit subsections310, 320 and configured to communicate fluidly with the channel 360.Furthermore, the annular housing subsection 330 preferably includes thefluid supply port 332 for supplying conditioning fluid therethrough tothe fluid supply chamber 340. Preferably, a conditioning fluid reservoir(not shown) supplies conditioning fluid to the fluid supply port 332 andtherethrough to the fluid supply chamber 340, wherefrom the conditioningfluid is drawn into the fluid delivery channels 360 and through theconduit structure containing the conduit coupler 300.

As can be seen in FIGS. 3 and 4, the port structures 214, 224 and 234and the delivery channels 360 are preferably configured to deliver theconditioning fluid into the conduit in a direction angled towards thesecond end in the same direction as the flow of the mixture stream.Additionally, these structures and channels are configured to deliverthe conditioning fluid into the conduit in an annular formation. Inorder to achieve this annular formation, each port structure can includea plurality of supply ports disposed in an annular formation around theconduit. Alternatively, each port structure can include one continuousport disposed circumferentially in the surface of the conduit in orderto completely surround the flow of the mixture stream at the point atwhich the mixture stream passes the port structure. In a preferredembodiment, this continuous port configuration makes the use of theannular housing 330 necessary in order to couple the conduit subsectionstogether.

The arrows 322 illustrate the flow of the gas-particle mixture throughthe conduit coupler 300. As shown, the flow is constricted near thefluid delivery channels 360 by the symmetric delivery of conditioningfluid into the coupler 300.

FIG. 4 is a flowchart illustrating one embodiment of a method 400 ofconditioning a reactive mixture in accordance with the principles of thepresent invention. As would be appreciated by those of ordinary skill inthe art, the protocols, processes, and procedures described herein maybe repeated continuously or as often as necessary to satisfy the needsdescribed herein. Additionally, although the steps of method 400 areshown in a specific order, certain steps may occur simultaneously or ina different order than is illustrated. Accordingly, the method steps ofthe present invention should not be limited to any particular orderunless either explicitly or implicitly stated in the claims.

At step 410, a mixture production system, such as the gas-particlemixture production system discussed above, produces a mixture stream. Itis contemplated that the mixture stream can be produced in a variety ofways. However, in a preferred embodiment, energy is delivered to aworking gas, thereby forming a plasma stream. The plasma stream is thenapplied to a precursor materia, such as powder particles. The powder ispreferably vaporized and the mixture stream is formed, preferablycomprising vaporized particles entrained therein.

At step 420, the mixture stream flows to and through a conduit system.The conduit system preferably comprises a conduit formed by a surfaceextending from a first end to a second end. A plurality of fluiddelivery features are preferably disposed along the conduit between thefirst end and the second end. The mixture stream flows through theconduit from the first end to the second end. It is contemplated thatthe mixture stream can be partially cooled and that vaporized particlesmay have already been partially or completely condensed prior tointroduction into the conduit.

At step 430, a conditioning fluid is delivered into the conduit whilethe mixture stream flows through the conduit. The conditioning fluid isdelivered through the plurality of delivery features. Each fluiddelivery feature delivers the conditioning fluid into the conduit in anannular formation in a direction angled towards the second end in thesame direction as the flow of the mixture stream, preferably providing asheath of conditioning fluid between the conduit surface and the mixturestream.

At step 440, the mixture stream flows from the conduit to a collectiondevice. In a preferred embodiment, the mixture stream at this point hasbeen sufficiently cooled so that the particles have condensed.

At step 450, the mixture stream flows through the collection device andthe collection device separates condensed particles from the mixturestream. As previously discussed, this separation can be achieved in avariety of ways.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding of theprinciples of construction and operation of the invention. As such,references herein to specific embodiments and details thereof are notintended to limit the scope of the claims appended hereto. It will beapparent to those skilled in the art that modifications can be made tothe embodiments chosen for illustration without departing from thespirit and scope of the invention.

1. A conduit system comprising: a conduit formed by a surface extendingfrom a first end to a second end, wherein the conduit is configured tochannel a mixture stream from the first end to the second end; aplurality of fluid delivery features disposed along the conduit betweenthe first end and the second end, wherein each fluid delivery feature isconfigured to deliver a conditioning fluid into the conduit in anannular formation in a direction angled towards the second end in thesame direction as the flow of the mixture stream, thereby providing asheath of conditioning fluid between the conduit surface and the mixturestream, wherein each fluid delivery feature comprises: a port structurefluidly coupled to the interior of the conduit and to deliver theconditioning fluid into the conduit in an annular formation in adirection angled towards the second end in the same direction as theflow of the mixture stream, and an annular housing disposed around theconduit and covering the port structure, wherein the annular housingcomprises a fluid supply port configured to supply the conditioningfluid to the port structure for delivery into the conduit.
 2. Theconduit system of claim 1, wherein the annular housing further comprisesa fluid supply chamber formed between the fluid supply port and the portstructure, the fluid supply chamber disposed circumferentially aroundconduit and the port structure, the fluid supply chamber beingconfigured to receive the conditioning fluid from the fluid supply portand supply the conditioning fluid circumferentially around and into theport structure.
 3. The conduit system of claim 1, wherein each portstructure comprises a plurality of fluid subports disposed in an annularformation around the conduit.
 4. The conduit system of claim 1, whereineach port structure comprises one continuous fluid port disposed in anannular formation around the conduit.
 5. The conduit system of claim 4,wherein the conduit comprises conduit subsections formed between eachport structure and adjacent conduit subsections are coupled together byone of the annular housings.
 6. The conduit system of claim 5, whereineach fluid delivery feature further comprises an indentation disposedcircumferentially in the conduit, the indentation being configured toreceive the annular housing and allow the annular housing to mate withthe conduit.
 7. The conduit system of claim 1, wherein the conduit has asubstantially constant diameter of approximately 2 inches.
 8. Theconduit system of claim 1, wherein the first end of the conduit isfluidly coupled to a mixture production system, the mixture productionsystem being configured to produce the mixture stream, the mixturestream comprising particles entrained within fluid.
 9. The conduitsystem of claim 8, wherein the mixture production system is configuredto produce the mixture stream by applying a plasma stream to a pluralityof particles, thereby vaporizing the particles.
 10. The conduit systemof claim 8, wherein a sampling device is fluidly coupled to the secondend of the conduit and is configured to receive the mixture stream fromthe second end of the conduit and separate condensed particles from themixture stream.
 11. A method of conditioning a mixture stream, themethod comprising: providing a conduit formed by a surface extendingfrom a first end to a second end, wherein a plurality of fluid deliveryfeatures are disposed along the conduit between the first end and thesecond end, and wherein each fluid delivery feature comprises a portstructure fluidly coupled to the interior of the conduit and an annularhousing disposed around the conduit and covering the port structure, theannular housing comprising a fluid supply port; flowing the mixturestream through the conduit from the first end to the second end; anddelivering a conditioning fluid into the conduit while the mixturestream flows through the conduit, wherein the conditioning fluid isflown through the fluid supply port of the annular housing to the portstructure where it is delivered through the port structure of each ofthe delivery features disposed along the conduit between the first endand the second end, each fluid delivery feature delivering theconditioning fluid into the conduit in an annular formation in adirection angled towards the second end in the same direction as theflow of the mixture stream, thereby providing a sheath of conditioningfluid between the conduit surface and the mixture stream.
 12. The methodof claim 11, wherein the conditioning fluid is an inert gas.
 13. Themethod of claim 11, wherein the annular housing further comprises afluid supply chamber formed between the fluid supply port and the portstructure, the fluid supply chamber disposed circumferentially aroundconduit and the port structure, the method further comprising the stepsof: the fluid supply chamber receiving the conditioning fluid from thefluid supply port; and the fluid supply chamber supplying theconditioning fluid circumferentially around and into the port structure.14. The method of claim 11, wherein each port structure comprises aplurality of fluid subports disposed in an annular formation around theconduit.
 15. The method of claim 11, wherein each port structurecomprises one continuous fluid port disposed in an annular formationaround the conduit.
 16. The method of claim 15, wherein the conduitcomprises conduit subsections formed between each port structure andadjacent conduit subsections are coupled together by one of the annularhousings.
 17. The method of claim 16, wherein each fluid deliveryfeature further comprises an indentation disposed circumferentially inthe conduit, the indentation being configured to receive the annularhousing and allow the annular housing to mate with the conduit.
 18. Themethod of claim 11, wherein the conduit has a substantially constantdiameter of approximately 2 inches.
 19. The method of claim 11, whereinthe first end of the conduit is fluidly coupled to a mixture productionsystem and the method further comprises the step of the mixtureproduction system producing the mixture stream, the mixture streamcomprising particles entrained within fluid.
 20. The method of claim 19,wherein the mixture production system produces the mixture stream byapplying a plasma stream to a plurality of particles, thereby vaporizingthe particles.
 21. The method of claim 19, wherein a sampling device isfluidly coupled to the second end of the conduit and the method furthercomprises the steps of: the sampling device receiving the mixture streamfrom the second end of the conduit; and the sampling device separatingcondensed particles from the mixture stream.